Bulletin Volume 198-205

Description

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1911 edition. Excerpt: ...are favorable for the growth of deep-rooted plants. The effect of close grazing on land occupied by the sand-hills mixed association (Pl. V, fig. 1), which often results in establishing a pure short-grass vegetation between the plants of sand sage, offers a most interesting example of this condition. The sage, which is not eaten, develops into large bushes, owing, doubtless, to the fact that it has no competitors for the water in the deeper layers of the soil. The short grasses also grow well on such land, since the taller grasses are kept down by grazing and can not displace the short grasses by overtopping them. CROP PRODUCTION ON LAND CHARACTERIZED BY DIFFERENT TYPES OF VEGETATION. CROP PRODUCTION ON SHORT-GRASS LAND. PHYSICAL CONDITIONS OF CULTIVATED SHORT-GRASS LAND. The physical conditions indicated by the presence of short grasses have already been discussed on pages 27 to 40. The water supply available for the plant is greatest in June and rapidly decreases in July, August, and September. The native plants, almost without exception, require only a short growing season. In eastern Colorado land characterized by short-grass vegetation is a loam which will easily take up 25 per cent of the water after a rain. The water penetrates slowly, and as a result of the ability of the soil to hold a high percentage moisture is usually confined to the upper foot or two of soil. Wherever the land is kept free from vegetation, as in summer tillage without crop, loss of water is greatly retarded and water may be conserved for a fall crop. WATER PENETRATION. Measurements were made to determine the comparative penetration and run-off from cultivated land and from the native sod, care being taken to avoid low places or places where there was a...show more